It is known in the art to provide an open ended oven with a moving conveyor belt that extends through the oven to move a food product through the oven. A typical conveyor oven includes a plurality of radiant heating elements located within the oven to provide a significant heat source to cook a food product that rides through the oven on the conveyor.
Other types of conveyor ovens bake a food product made from dough by adding steam to the stream of hot air and imparting the mixture upon the product as it moves through the oven on a conveyor. This type of oven includes two open ends that are connected with a conveyor. The oven imparts air and saturated steam upon a dough product, such as a bagel, to bake the bagel as it moves through the oven on the conveyor. By exposing the bagel to a moisture-rich steam environment, the bagel is properly baked while allowing it to obtain the familiar hard and shiny exterior surface with the soft internal breading.
Although suitable for baking certain types of dough products, the moisture rich saturated steam makes this type of oven unsuitable for broader applications, namely the cooking of other types of food products, such as full sandwiches, vegetables and pizza. The high moisture content within a steam-based oven can significantly wet the exterior surfaces of the sandwich or the pizza, ruining the food products.
Ceramic or similar types of heating elements are sometimes used within an open ended conveyor style oven to provide sufficient radiant heat to cook a food product that moves through the oven on a conveyor. These types of ovens are currently used in many restaurants that sell custom made heated sandwiches. A problem in ovens with ceramic heating elements is that in moisture-rich environments, the heating elements have a tendency to crack or otherwise brittle fracture, which reduces the useful life of a ceramic heating element. This phenomenon may occur when moisture enters gaps or other imperfections inherently present in typical ceramic heaters during periods when the heaters are cooled to ambient temperature. If the heaters rapidly warm, the moisture may boil before it has time to migrate out of the heater. The boiling of the moisture causes rapid expansion and increases the pressure within the gap, which may cause cracking or fracture. It is therefore desired to provide a method to heat an oven that includes ceramic or other similar heating elements to avoid problems with cracking or brittle fracture.
It takes a significant amount of time and energy to heat a typical conveyor type oven to normal operating temperature, and when the oven is operating at normal temperature, the oven requires a significant amount of energy to operate. There are often periods when the oven will be maintained at operating temperature because it is expected that the oven will again be used to cook a food product, without an immediate need to cook a food product. While it is often possible to manually reduce the operating temperature of the oven to conserve energy, it is desired to provide an improved mechanism for conserving energy when the oven is not being used
As is known, the exterior surfaces of a conveyor oven typically are heated to temperatures significantly above ambient when the oven is at a normal operating temperature. As can be understood, and has been experienced by many restaurant industry employees, the elevated temperatures of the external surfaces of the oven may lead to burns if the employee's exposed skin contacts the oven's external surface during operation. Accordingly, it is desired to provide an oven that has external surfaces that will not cause burn injuries if they are accidentally contacted by exposed skin when the oven is at normal operating temperature.